Hello, my garage is currently powered via a single 15 amp circuit through some outdoor Romex that is buried in the ground between the back of my house (it goes through the brick and into a junction box on the ceiling of my basement (I would like to move this box to put in a bathroom and figured since I was here...)) Believe it or not my garage has a terra cotta pipe around 6" in diameter that once held oil fill pipes (one fill and one vent) that terminated in an oil tank in my basement. I have since ripped out the oil pipes and am now thinking about running some wire through the terracotta instead of having it go through my yard.

Here are my questions, thanks in advance for any answers! ->
1. I would like to put a sub-panel in my garage that I can use for the existing 15 amp circuit plus give me space for future expansion of an electric car charging station - what size sub-panel will give me that headroom? 50amp? 60amp?
2. Would it be code to run a piece of pvc through the terra cotta pipe such that I could then run the wire for my sub-panel through that pvc? I am planning on pouring waterproof cement into the terracotta after I put in the pvc to prevent animals and any potential water from coming down the terracotta.
3. If #2 is doable, what type and gauge of wire should I install in the pvc to service the sub-panel for the amount of current needed in #1? 6 gauge? The distance from my main panel in the basement to this new sub-panel (assuming I can go through the terra cotta would be approximately 50')
4. While my garage is nice and dry (certainly at the height where I would mount the sub-panel) it will just be on the wall of my garage. Would I need an outdoor sub-panel or could I use an indoor sub-panel per code? My main is a square D.

Thanks again,
Jeff

 

I don't see any code reasons why a cable or a conduit could not be sleeved in the terra cotta.

The feed to the shed will be sized by what you plan to use the shed for. You may be able to use something much smaller than a 60 amp feeder.

If the panel is inside you do not need an outside rated panel.

 

Okay thanks! Yeah a friend told me that for a electric car charger you need 60 amps.

 

Make sure the terra cotta pipe is deep enough to meet code. You will need a minimum of 18 inches of cover if the wire is run within PVC conduit even if placed in the terra cotta pipe.

 

Yeah it's an interesting setup, the entire terra cotta is encased in cement, with one end coming up under the garage floor, and the other coming out about two feet above the floor in the basement. It's at about a 45 degree angle down. The garage is above the basement, almost at the level of the first floor of the house above the basement. Assuming the concrete protecting the terra cotta would qualify as protection enough if somebody went digging in the yard.